Deviation detection in mobile transit systems

ABSTRACT

In one embodiment, a mobile device or a network device is configured to identify when a transit vehicle deviates from a transit path. The mobile device is configured to perform a positioning technique to generate data indicative of the location of a mobile device. Based on the location of the mobile device, a path is identified. The path is associated with an estimated path width based on the classification of the path and/or the accuracy of the positioning technique. A target route is calculated using the estimated path width. As the transit vehicle travels, the target route is compared to the location of the mobile device. If the mobile device and or transit vehicle deviates from the target route, a message is generated. The message may indicate that the transit vehicle is being re-routed and/or recommends the computation of a new path.

FIELD

The following disclosure relates to location tracking in transportationsystems.

BACKGROUND

Transportation systems include automobiles, buses, trains, and othermodes of transportation. Example transportation systems include thepublic transit systems of many metropolitan areas. In a transit system,the transit vehicle typically follows a set route. The route is a pathfrom station to station or from stop to stop.

Occasionally, transit vehicles do not follow the scheduled routes. Inthe example of bus routes, a bus may be re-routed because of a trafficincident (e.g., an accident or congestion), a flood, an event (e.g., aparade or motorcade), or a variety of reasons. In the example of trainroutes, track construction, or accident may cause the train to use adifferent line of tracks. Sometimes the re-routing is scheduled andsometimes the re-routing occurs without warning.

Transit vehicles may also deviate from schedules because of delaysarising from route deviations or re-routes. Ideally, each vehicle on theroute arrives at each station or stop on the path according to a preciseschedule. However, several events can disrupt the schedule. In theexample of bus routes, an accident or congestion can cause traffic,which delays the buses. In addition, when many riders have congregatedat a stop, the bus is delayed as riders enter the bus and scan theirfare cards. In the example of train routes, heavy usage or interferenceby other trains causes delays for riders to board and disembark.

These usage types of delays tend to snowball. When a bus is late, moreriders aggregate at a stop. When the bus arrives, more time is requiredto board all of the extra riders. Fewer riders are at the stop when thenext bus arrives, which causes the next bus to spend less time at thespot and tend to catch up with the first bus.

Both temporal and spatial deviations of transit vehicles impair theability of users to predict when the transit vehicle will arrive at astop or station and/or locate the new location of the stop or station.

SUMMARY

In one embodiment, a mobile device or a network device is configured toidentify when a transit vehicle deviates from a transit path. The mobiledevice is configured to perform a positioning technique to generate dataindicative of the location of a mobile device. Based on the location ofthe mobile device, a path is identified. The path is associated with anestimated path width based on the classification of the path and/or theaccuracy of the positioning technique. A target route is calculatedusing the estimated path width. As the transit vehicle travels, thetarget route is compared to the location of the mobile device. If themobile device and or transit vehicle deviates from the target route, amessage is generated. The message may indicate that the transit vehicleis being re-routed and/or recommends the computation of a new path.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention are described herein withreference to the following drawings.

FIG. 1 illustrates an exemplary navigation system for route deviationdetection.

FIG. 2 illustrates an example transit path.

FIG. 3 illustrates an example target route for the transit path of FIG.2.

FIG. 4 illustrates another example target route for the transit path ofFIG. 2.

FIG. 5 illustrates an example rerouted path for the transit path of FIG.2.

FIG. 6 illustrates an exemplary mobile device of the navigation systemof FIG. 1.

FIG. 7 illustrates an exemplary server of the navigation system of FIG.1.

FIG. 8 illustrates an example flowchart for route deviation detection.

DETAILED DESCRIPTION

The following embodiments include the detection in real time of when andwhere a mobile transit object deviates from a scheduled route or ahistorical route. The scheduled route may be a series of estimated timespaired with geographic locations for transit stops or stations. Thehistorical route may be an average of recorded times and/or geographiclocations from past routes on the transit system. The deviation may beeither spatial or temporal. Once the deviation is identified, thedeviation may be utilized to choose a new route or derive the new routefor display to users. In addition, the deviating location points may beused to construct a new route leg, a new stop, and/or new schedules forthe transit system. The new information may be transmitted to users orthe transit system administrator.

FIG. 1 illustrates an exemplary navigation system 120 for routedeviation detection. The navigation system 120 includes a map developersystem 121, a mobile device 122, a workstation 128, and a network 127.Additional, different, or fewer components may be provided. For example,many mobile devices 122 and/or workstations 128 may connect with thenetwork 127.

The mobile device 122 is configured to calculate the geographic locationof the mobile device 122. The geographic location may be determinedthrough Global Positioning System (GPS) or another technique. The mobiledevice 122 generates a message including the geographic location andsends the message to the server 125.

The server 125 is configured to receive the message including dataindicative of the geographic location of the mobile device 122 andidentify a route or path that the mobile device 122 is likely following.The route may be a bus route stored ahead of time by server 125. Theselected route may be estimated based on the geographic location of themobile device 122. For example, the server 125 may compare a list oflocations for paths of bus routes to the geographic location of themobile device 122. Multiple locations over time of the mobile device 122may be used to resolve any ambiguity regarding multiple bus routes at agiven location of the mobile device 122. Alternatively, the route may beidentified in the message received from the mobile device.

The database 123 is configured to store a list of routes. The routes maybe bus routes, train routes, or other types of routes. Each route maytraverse different types of paths. For example, a bus route may follow amajor highway for one portion of the route and a residential street foranother portion of the route. The database 123 may describe each type ofpath on the route. In one example, the database 123 lists characteristicinformation for the path. The characteristic information includes thetype of the path (e.g., highway, street) and/or the size of the path(e.g., 2 lanes, 20 feet).

The server 125 is configured to access the characteristic informationfor the path from the database 123. The server 125 determines a targetroute for the path. The path is a line and the target route is an areathat includes the path. The target route is sized according to thecharacteristic information. The target route has a width based on thecharacteristic information. For example, the target route for a highwayis generally wider than the target route for a residential street, andthe target route for a three lane road is wider than the target routefor a two lane road.

The target route may also be adjusted according to the accuracy of thepositioning technique of the mobile device 122. For example, when GPS isused, accuracy depends on the line of sight to the sky. GPS performsbetter in open rural areas than in urban areas or areas with othercover. The database 123 may include data indicative of GPS accuracy. Thedata indicative of GPS accuracy may describe whether or not specificgeographic locations are considered an urban canyon, which is defined asan area dominated by tall buildings. Tall buildings may partially blockGPS signals. The data indicative of GPS accuracy may indicate city orrural, may be a distance, or may be a value on a rating scale (e.g., 1to 10).

The data indicative of GPS accuracy may be derived from a building modelstored in the database 123. The building model describes thetwo-dimensional footprint or the three-dimensional size of buildings.The server 125 may access the building model and compare the relativesizes of buildings near the geographic location of the mobile device 122to a threshold level. Alternatively, the GPS accuracy for differentlocations is stored and accessed, received from the mobile device 122,or otherwise calculated.

The target route may also be sized according to a baseline calculatedfrom historical data. The historical data may be location pointscollected from vehicles following the same route. For example, thetransit vehicles may report a current geographic positioned at a regularinterval (e.g., every minute, every 20 seconds). Alternatively, thelocation points may be collected in response to requests sent from theserver 125. The server 125 may be configured to filter the data. Forexample, outliers may be removed. In addition, the server 125 mayaverage sets of collected location points to calculate the baseline. Thesets of collected location points may be grouped in clusters dependenton the proximity of the location points with respect to one another.

The server 125 is configured to determine whether the location of themobile device 122 deviates from the path based on a comparison of thecurrent geographic location of the mobile device 122 to the targetroute. The current geographic location may be the same location used toselect the path. However, often, the current geographic location may bedetermined later in time than the location used to select the path. Thecurrent geographic location may be determined periodically. Periodicallyis defined as over time at intervals such that the intervals are notnecessarily equally spaced and can be of any duration. Alternatively,the intervals may be evenly spaced.

The server 125 may calculate a width for the target route and comparethe width or half of the width to a distance from the current geographiclocation of the mobile device 122 to the center of the target route,which is the location of the path.

When the half of the width exceeds the distance, the mobile device 122falls within the target route. Therefore, the mobile device 122 has notdeviated from the target route. However, when the distance exceeds halfof the width, the mobile device 122 has deviated from the target route.The server 125 may determine from the deviation or the size of thedeviation that the transit vehicle has been re-routed.

The server 125 may request additional location points from the mobiledevice 122 in or to construct the rerouted path. For example, inresponse to the server 125 determining that the mobile device 122 hasdeviated from the target route, the server 125 may generate a requestfor subsequent geographic position measurements to be made by the mobiledevice 122. The additional position data may be used to construct there-routed path, both temporally and spatially, of the transit vehicle.

The server 125 may generate an error message that indicates that themobile device 122 has left the target route. The error message may besent to a transit authority server as an indication that the transitvehicle is being rerouted. The error message may be sent to individualuser devices by way of a bus tracking application or navigationapplication. The user devices may be configured to adjust stop times orstop locations according to the error message.

In the alternative or in addition to spatial deviations, the server 125may be configured to identify temporal deviations. The server 125 isconfigured to access a schedule for the transit route for an expectedtime for the current geographic location. The server 125 is configuredto calculate a temporal deviation value based on the comparison of theexpected time to a current time. The server 125 determines subsequentstop times for the transit route based on the temporal deviation value.The temporal deviation may be adjusted according to an adjustment valuebased on observed noise related to traffic or weather.

The developer system 121 includes a server 125 and a database 123. Theoptional workstation 128 is a general purpose computer includingprogramming specialized for the following embodiments. The workstation128 includes at least a memory, a processor, and a communicationinterface. The developer system 121 may include computer systems andnetworks of a system operator such as NAVTEQ or Nokia Corporation. Thegeographic database 123 may be partially or completely stored in themobile device 122.

The developer system 121, the workstation 128, and the mobile device 122are coupled with the network 127. The phrase “coupled with” is definedto mean directly connected to or indirectly connected through one ormore intermediate components. Such intermediate components may includehardware and/or software-based components.

The mobile device 122 is a smart phone, a mobile phone, a personaldigital assistant (“PDA”), a tablet computer, a notebook computer, apersonal navigation device (“PND”), a portable navigation device, and/orany other known or later developed mobile device.

The optional workstation 128 is a general purpose computer includingprogramming specialized for providing input to the server 125. Forexample, the workstation 128 may provide settings for the server 125.The settings may include a value for the predetermined interval that theserver 125 requests mobile device 122 to relay current geographiclocations. The workstation 128 may be used to enter data indicative ofGPS accuracy to the database 123.

FIGS. 2-5 show example operation of the system of FIG. 1 relative topaths or routes. FIG. 2 illustrates a transit path 130. The transit path130 includes nodes 131 and segments 132. The nodes 131 may be defined asa cluster of points. The nodes 131 may be at predetermined locations,such as transit stops. Alternatively, the nodes 131 may be calculatedbased on location data collected by the mobile device 122 or multiplemobile devices.

The server 125 may be configured to define the transit path 130according to historical data. For example, the server 125 may beconfigured to compare the relative locations of data points in thelocation data to identify sets of data points. The sets of data pointsmay be within a threshold distance from one another. In one example, theserver 125 selects a location data point and counts the number oflocation data points within the threshold distance from the firstselected data point. If the number of location data points exceeds aminimum number (e.g., 2, 5, 10), the set of data points are identifiedby the server 125 as a cluster. The cluster may be stored as ageographic range including the set of data points or the cluster may bestored as a point that is the average of the set of data points. Thedistance between clusters may be arbitrary as a result of dependence onthe clustering of the data points. Alternatively, the server 125 maytarget a specific distance between clusters.

FIG. 3 illustrates an example target route for the transit path 130 ofFIG. 2. The path may be a dimensionless line between two points.Alternatively, the target route is an area with a width associated withthe transit path 130. The target route may have different widths atdifferent locations. For example, the example target route shown in FIG.3 includes three portions 141 a-c. The first portion 141 a of the targetroute has a width smaller than the second portion 141 b of the targetroute.

The target route may include an inner width and an outer width. In thefirst portion 141 a, the inner width is between boundaries 142, and theouter width is between boundaries 144. The inner width may be definedaccording to a functional classification of the path. The functionalclassifications may be defined according to a custom classificationsystem defined using workstation 128 and stored in database 123.Alternatively, the functional classifications may be defined accordingto a predetermined classification system. Table 1 lists exampleclassification systems.

TABLE 1 U.S. Long Distance Simple System Complex System Roads HighwayTags Arterial Road Interstates Interstate Motorway Expressway CollectorRoad Principal Arteries Federal Highway Trunk Local Road Minor ArteriesState Highway Primary Major Collector County Highway Secondary MinorCollector Local Road Tertiary Local Road Residential

One example of a simple system includes the functional classificationmaintained by the United States Federal Highway administration. Thesimple system includes arterial roads, collector roads, and local roads.The functional classifications of roads balance between accessibilityand speed. An arterial road has low accessibility but is the fastestmode of travel between two points. Arterial roads are typically used forlong distance travel. Collector roads connect arterial roads to localroads. Collector roads are more accessible and slower than arterialroads. Local roads are accessible to individual homes and business.Local roads are the most accessible and slowest type of road.

An example of a complex functional classification system is the urbanclassification system. Interstates include high speed and controlledaccess roads that span long distances. The arterial roads are dividedinto principle arteries and minor arteries according to size. Thecollector roads are divided into major collectors and minor collectorsaccording to size.

Another example functional classification system divides long distanceroads by type of road or the entity in control of the highway. Thefunctional classification system includes interstate expressways,federal highways, state highways, local highways, and local accessroads. Another functional classification system uses the highway tagsystem in the Open Street Map (OSM) system. The functionalclassification includes motorways, trunk roads, primary roads, secondaryroads, tertiary roads, and residential roads.

Alternatively, the inner width may be defined according to the width ofthe roads or the number of lanes of the roads. For example, the database123 may list road width or lane quantities. The server 125 may accessthe database for the road width according to the geographic locationreported by the mobile device 122. The road width may be used as aninitial value of the target route.

The outer width between boundaries 144 may be determined according tothe accuracy of the location determination technique. The accuracy ofthe location determination technique may be measured directly or may beinferred from the geographic surroundings of the mobile device 122 orother source. The database 123 may store geographic locations of urbancanyons where tall buildings affect the accuracy of GPS and otherlocation determination techniques.

The outer width between boundaries 144 may be calculated form thelocation of the inner width between boundaries 142. In one example, theouter width is defined to be 25% wider than the inner width when nourban canyon is present and 50% wider than the inner width when an urbancanyon is present. The outer width may be adjusted by any percentage orany distance. In another example, the outer width may be adjusted in anamount proportionally to a scale factor (e.g., from 1 to 10) of theaccuracy of the location determination technique. The scale factor (k)may be stored by the mobile device 122 and included in the messagereporting the location of the mobile device 122. The adjustment may be(k*10) percent adjustment or another relationship.

In another embodiment, the width of the target area depends on thedetected location of the mobile device 122. The center line 140represents a center of the targeted route. Boundaries 144 define thewidth of the target area when the mobile device 122 is located within afirst predetermined distance from the center line 140 or from one of theboundaries 144. When the mobile device 122 comes within a secondpredetermined distance of one of the boundaries 144, the server 125calculates a new target width which takes into consideration theaccuracy of the location determination technique.

The example target route shown in FIG. 3 provides an example where thetransit path 130 has a first width at first portion 141 a and a secondwidth at second portion 141 b. The difference between the inner width ofthe first portion 141 a and the second portion 141 b is illustrated asW1. At the third portion 141 c, the transit path 130 returns to thefirst width.

FIG. 4 illustrates another example target route for the transit path 130of FIG. 2. In the example shown in FIG. 4, the inner width is constantover the three portions 141 a-c. However, the outer width changesaccording to the accuracy of the location determination system. Theouter width in the second portion 141 b is greater than the outer widthin the first portion 141 a.

The accuracy of the location determination system may be definedaccording to a circular error probability. The circular errorprobability is defined by a circle or radius of a circle of a geographicarea of possible geographic locations. Each geographic locationdetermined by the mobile device 122 could correspond to any locationwithin the circle of error probability. The circular error probabilitymay be statistically determined using a series of location data taken ina short time. The circular error probability may be a value stored bythe mobile device 122 set at the time of manufacture.

FIG. 5 illustrates an example rerouted path for the transit path of FIG.2. A map 150 includes an expected transit path 130 and an alternateroute 151 that is re-routed from the transit path 130. The server 125 orthe mobile device 122 may be configured to detect when the transitvehicle has left the expected transit path 130 for the alternate route151. Either or both of the expected transit path 130 and the alternateroute 151 may be stored as clusters of collected data as shown in FIG.5.

The map 150 may be displayed on the mobile device 122 to a user of thetransit system. For example, the map 150 may be accessed using a mobileapplication for display transit system routes. The mobile applicationinforms riders when a bus or other transit vehicle has deviated from theexpected transit path 130. The map 150 may also illustrate a graphicalindication that the expected transit path 130 is not being followed. Forexample, clusters or stops indicated on the expected transit path 130may be grayed out or crossed out with an “X”.

The computing resources for the detection of transit route deviation maybe divided between the server 125 and the mobile device 122. In someembodiments, the server 125 performs a majority of the processing(“server-based embodiments”). In other embodiments, the mobile device122 or the workstation 128 performs a majority of the processing(“endpoint-based embodiments”). In addition, the processing is dividedsubstantially evenly between the server 125 and the mobile device 122 orworkstation 128 (“hybrid embodiments”).

In the server-based embodiments as discussed above, the server 125 isconfigured to receive location data from the mobile device 122. From thelocation data, the server 125 is configured to determine a target routeusing previously stored data regarding the classification or size of apath including or near the location data. When the mobile device 122subsequently deviates from the path as determined from additionallocation data received from the mobile device 122, the server 125 isconfigured to identify the deviation and generate a message describingthe deviation. In the endpoint-based embodiments or hybrid embodiments,one or more of these features are performed by the mobile device 122.

FIG. 6 illustrates an exemplary mobile device 122 of the navigationsystem of FIG. 1. The mobile device 122 may be referred to as anavigation device. The mobile device 122 includes a controller 200, amemory 204, an input device 203, a communication interface 205, positioncircuitry 207, and a display 211. Additional, different, or fewercomponents are possible for the mobile device 122.

The memory 204 is configured to store target routes for a plurality oftransit routes. The target routes may be calculated and stored inadvance. The target routes may be associated with geographic locationsor geographic ranges.

The controller 200 is configured to receive data indicative of thelocation of the mobile device 122 from the position circuitry 207. Thecontroller 200 identifies one of the target routes based on the locationof the mobile device 122. The controller 200 compares the target routeto the location or a subsequent location of the mobile device 122. Thecomparison of the target route and the location of the mobile device 122determines whether the location of the mobile device 122 deviates fromthe target route.

The positioning circuitry, which is an example of a positioning system,is configured to determine a geographic position of the mobile device122. The positioning circuitry 207 may include sensing devices thatmeasure the traveling distance, speed, direction, and so on, of themobile device 122. The positioning system may also include a receiverand correlation chip to obtain a GPS signal. The positioning circuitrymay include an identifier of a model of the positioning circuitry 207.The controller 200 may access the identifier and query a database or awebsite to retrieve the accuracy of the positioning circuitry 207 basedon the identifier. The positioning circuitry 207 may include a memory orsetting indicative of the accuracy of the positioning circuitry.

Alternatively or additionally, the one or more detectors or sensors inthe positioning circuitry 207 may include an accelerometer and/or amagnetic sensor built or embedded into or within the interior of themobile device 122. The accelerometer is operable to detect, recognize,or measure the rate of change of translational and/or rotationalmovement of the mobile device 122. The magnetic sensor, or a compass, isconfigured to generate data indicative of a heading of the mobile device122. Data from the accelerometer and the magnetic sensor may indicateorientation of the mobile device 122. The mobile device 122 receiveslocation data from the positioning system. The location data indicatesthe location of the mobile device 122.

The positioning circuitry 207 may include a Global Positioning System(GPS), Global Navigation Satellite System (GLONASS), or a cellular orsimilar position sensor for providing location data. The positioningsystem may utilize GPS-type technology, a dead reckoning-type system,cellular location, or combinations of these or other systems. Thepositioning circuitry 207 may include suitable sensing devices thatmeasure the traveling distance, speed, direction, and so on, of themobile device 122. The positioning system may also include a receiverand correlation chip to obtain a GPS signal. The mobile device 122receives location data from the positioning system. The location dataindicates the location of the mobile device 122. The accuracy of thepositioning technology affects the width of the target route.

The input device 203 may be one or more buttons, keypad, keyboard,mouse, stylist pen, trackball, rocker switch, touch pad, voicerecognition circuit, or other device or component for inputting data tothe mobile device 122. The input device 203 and the display 211 may becombined as a touch screen, which may be capacitive or resistive. Thedisplay 211 may be a liquid crystal display (LCD) panel, light emittingdiode (LED) screen, thin film transistor screen, or another type ofdisplay.

FIG. 7 illustrates an exemplary server 125 of the navigation system ofFIG. 1. The server 125 includes a processor 300, a communicationinterface 305, and a memory 301. The server 125 may be coupled to adatabase 123 and a workstation 310. The database 123 may be a geographicdatabase as discussed above. The workstation 310 may be used as an inputdevice for the server 125. In addition, the communication interface 305is an input device for the server 125. The communication interface 305receives data indicative of use inputs made via the workstation 128 orthe mobile device 122.

The communication interface 305 is configured to receive periodic dataindicative of a location of the mobile device 122 from the mobile device122. The processor 300 is configured to analyze the periodic data toidentify a path near the mobile device 122. The processor 300 may selectthe path nearest to the mobile device 122 from a set of paths stored inmemory 301 or database 123.

The processor 300 is also configured calculate a target route based oncharacteristic information for the path. The characteristic informationmay include the actual width of the path. The path widths may bepredetermined and stored in the database 123. Alternatively, the pathwidths may be based on detected locations over time. The characteristicinformation may include a classification of the path. The database 123may include a lookup table that correlates path classifications and pathwidths.

The processor 300 is configured to determine whether the mobile device122 deviates from the path based on a comparison of the location of themobile device 122 to the target route. The comparison may involvecalculating a distance between the center of the path width and thegeographic location received from the mobile device 122. The comparisonmay involve comparing a threshold distance to the distance from thecenter of the path to the geographic location received from the mobiledevice 122. The threshold distance may be set according to thedetermined path width. The threshold distance and/or path width may befurther adjusted according to an accuracy level of the periodic dataindicative of the location of the mobile device. The accuracy level maybe tied to the mobile device 122 or the positioning technique used bythe mobile device 122.

The controller 200 and/or processor 300 may include a general processor,digital signal processor, an application specific integrated circuit(ASIC), field programmable gate array (FPGA), analog circuit, digitalcircuit, combinations thereof, or other now known or later developedprocessor. The controller 200 and/or processor 300 may be a singledevice or combinations of devices, such as associated with a network,distributed processing, or cloud computing.

The memory 204 and/or memory 301 may be a volatile memory or anon-volatile memory. The memory 204 and/or memory 301may include one ormore of a read only memory (ROM), random access memory (RAM), a flashmemory, an electronic erasable program read only memory (EEPROM), orother type of memory. The memory 204 and/or memory 301 may be removablefrom the mobile device 100, such as a secure digital (SD) memory card.

The communication interface 205 and/or communication interface 305 mayinclude any operable connection. An operable connection may be one inwhich signals, physical communications, and/or logical communicationsmay be sent and/or received. An operable connection may include aphysical interface, an electrical interface, and/or a data interface.The communication interface 205 and/or communication interface 305provides for wireless and/or wired communications in any now known orlater developed format.

FIG. 8 illustrates an example flowchart for route deviation detection.The process of the flowchart may be performed by the mobile device 122and controller 200 and/or server 125 and processor 300, which may bereferred to alternatively as the controller in the followingdescription. Alternatively, another device may be configured to performone or more of the following acts. Additional, fewer, or different actsmay be included.

At act S101, the controller receives data indicative of the location ofthe mobile device 122. The data may include longitude and latitudecoordinates. The location data may be a running average of sensor dataover a short period of time. The location data may be filtered to removenoise or outliers. The location data may be reported periodically orbased on location detection command.

At act S103, the controller identifies a path based on the location ofthe mobile device 122. The paths may be stored according to ranges ofgeographic locations. The controller may select the path closest to themobile device 122. In some scenarios, multiple routes may overlap and,the controller may be configured to select multiple paths or distinguishbetween routes based on multiple different locations of the mobiledevice 122.

At act S105, the controller accesses characteristic information for thepath. The characteristic information may be any information used todescribe the path and determinative of the size of the path. Thecharacteristic information may be the explicit size of the path, or thecharacteristic information may include a type for the path. In oneexample, the type may be either a large road or a small road. In anotherexample, the type may be the functional classification. Thecharacteristic information or the path width may also depend on aprecision factor for the positioning technique that determined thelocation of the mobile device 122. At act S107, the controllercalculates a target route from the characteristic information andhistorical data for the path.

At act S109, the controller determines whether the location of themobile device 122 deviates from the path. The controller comparesperiodic location data from the mobile device 122 to the target routebased on the characteristic information for the path. The controller maydetermine whether a particular location point or a current locationpoint in the periodic location data falls within the target route. Thecontroller may determine how far the particular location point or thecurrent location point is from the boundary of the target route or thecenter of the target route.

If the mobile device 122 leaves the target route area, a deviation isidentified. The controller is configured to generate a message inresponse to the deviation. The message may be a message to mobiledevices that indicates that transit vehicles on the path are beingrerouted. The message may be a transit map used to track the location oftransit vehicles. The message may include an estimated arrival time.

The network 127 may include wired networks, wireless networks, orcombinations thereof. The wireless network may be a cellular telephonenetwork, an 802.11, 802.16, 802.20, or WiMax network. Further, thenetwork 127 may be a public network, such as the Internet, a privatenetwork, such as an intranet, or combinations thereof, and may utilize avariety of networking protocols now available or later developedincluding, but not limited to TCP/IP based networking protocols.

While the non-transitory computer-readable medium is described to be asingle medium, the term “computer-readable medium” includes a singlemedium or multiple media, such as a centralized or distributed database,and/or associated caches and servers that store one or more sets ofinstructions. The term “computer-readable medium” shall also include anymedium that is capable of storing, encoding or carrying a set ofinstructions for execution by a processor or that cause a computersystem to perform any one or more of the methods or operations disclosedherein.

In a particular non-limiting, exemplary embodiment, thecomputer-readable medium can include a solid-state memory such as amemory card or other package that houses one or more non-volatileread-only memories. Further, the computer-readable medium can be arandom access memory or other volatile re-writable memory. Additionally,the computer-readable medium can include a magneto-optical or opticalmedium, such as a disk or tapes or other storage device to capturecarrier wave signals such as a signal communicated over a transmissionmedium. A digital file attachment to an e-mail or other self-containedinformation archive or set of archives may be considered a distributionmedium that is a tangible storage medium. Accordingly, the disclosure isconsidered to include any one or more of a computer-readable medium or adistribution medium and other equivalents and successor media, in whichdata or instructions may be stored.

In an alternative embodiment, dedicated hardware implementations, suchas application specific integrated circuits, programmable logic arraysand other hardware devices, can be constructed to implement one or moreof the methods described herein. Applications that may include theapparatus and systems of various embodiments can broadly include avariety of electronic and computer systems. One or more embodimentsdescribed herein may implement functions using two or more specificinterconnected hardware modules or devices with related control and datasignals that can be communicated between and through the modules, or asportions of an application-specific integrated circuit. Accordingly, thepresent system encompasses software, firmware, and hardwareimplementations.

In accordance with various embodiments of the present disclosure, themethods described herein may be implemented by software programsexecutable by a computer system. Further, in an exemplary, non-limitedembodiment, implementations can include distributed processing,component/object distributed processing, and parallel processing.Alternatively, virtual computer system processing can be constructed toimplement one or more of the methods or functionality as describedherein.

Although the present specification describes components and functionsthat may be implemented in particular embodiments with reference toparticular standards and protocols, the invention is not limited to suchstandards and protocols. For example, standards for Internet and otherpacket switched network transmission (e.g., TCP/IP, UDP/IP, HTML, HTTP,HTTPS) represent examples of the state of the art. Such standards areperiodically superseded by faster or more efficient equivalents havingessentially the same functions. Accordingly, replacement standards andprotocols having the same or similar functions as those disclosed hereinare considered equivalents thereof.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, and it can bedeployed in any form, including as a standalone program or as a module,component, subroutine, or other unit suitable for use in a computingenvironment. A computer program does not necessarily correspond to afile in a file system. A program can be stored in a portion of a filethat holds other programs or data (e.g., one or more scripts stored in amarkup language document), in a single file dedicated to the program inquestion, or in multiple coordinated files (e.g., files that store oneor more modules, sub programs, or portions of code). A computer programcan be deployed to be executed on one computer or on multiple computersthat are located at one site or distributed across multiple sites andinterconnected by a communication network.

The processes and logic flows described in this specification can beperformed by one or more programmable processors executing one or morecomputer programs to perform functions by operating on input data andgenerating output. The processes and logic flows can also be performedby, and apparatus can also be implemented as, special purpose logiccircuitry, e.g., an FPGA (field programmable gate array) or an ASIC(application specific integrated circuit).

As used in this application, the term ‘circuitry’ or ‘circuit’ refers toall of the following: (a)hardware-only circuit implementations (such asimplementations in only analog and/or digital circuitry) and (b) tocombinations of circuits and software (and/or firmware), such as (asapplicable): (i) to a combination of processor(s) or (ii) to portions ofprocessor(s)/software (including digital signal processor(s)), software,and memory(ies) that work together to cause an apparatus, such as amobile phone or server, to perform various functions) and (c) tocircuits, such as a microprocessor(s) or a portion of amicroprocessor(s), that require software or firmware for operation, evenif the software or firmware is not physically present.

This definition of ‘circuitry’ applies to all uses of this term in thisapplication, including in any claims. As a further example, as used inthis application, the term “circuitry” would also cover animplementation of merely a processor (or multiple processors) or portionof a processor and its (or their) accompanying software and/or firmware.The term “circuitry” would also cover, for example and if applicable tothe particular claim element, a baseband integrated circuit orapplications processor integrated circuit for a mobile phone or asimilar integrated circuit in server, a cellular network device, orother network device.

Processors suitable for the execution of a computer program include, byway of example, both general and special purpose microprocessors, andanyone or more processors of any kind of digital computer. Generally, aprocessor receives instructions and data from a read only memory or arandom access memory or both. The essential elements of a computer are aprocessor for performing instructions and one or more memory devices forstoring instructions and data. Generally, a computer also includes, orbe operatively coupled to receive data from or transfer data to, orboth, one or more mass storage devices for storing data, e.g., magnetic,magneto optical disks, or optical disks. However, a computer need nothave such devices. Moreover, a computer can be embedded in anotherdevice, e.g., a mobile telephone, a personal digital assistant (PDA), amobile audio player, a Global Positioning System (GPS) receiver, to namejust a few. Computer readable media suitable for storing computerprogram instructions and data include all forms of non-volatile memory,media and memory devices, including by way of example semiconductormemory devices, e.g., EPROM, EEPROM, and flash memory devices; magneticdisks, e.g., internal hard disks or removable disks; magneto opticaldisks; and CD ROM and DVD-ROM disks. The processor and the memory can besupplemented by, or incorporated in, special purpose logic circuitry.

To provide for interaction with a user, embodiments of the subjectmatter described in this specification can be implemented on a devicehaving a display, e.g., a CRT (cathode ray tube) or LCD (liquid crystaldisplay) monitor, for displaying information to the user and a keyboardand a pointing device, e.g., a mouse or a trackball, by which the usercan provide input to the computer. Other kinds of devices can be used toprovide for interaction with a user as well; for example, feedbackprovided to the user can be any form of sensory feedback, e.g., visualfeedback, auditory feedback, or tactile feedback; and input from theuser can be received in any form, including acoustic, speech, or tactileinput.

Embodiments of the subject matter described in this specification can beimplemented in a computing system that includes a back end component,e.g., as a data server, or that includes a middleware component, e.g.,an application server, or that includes a front end component, e.g., aclient computer having a graphical user interface or a Web browserthrough which a user can interact with an implementation of the subjectmatter described in this specification, or any combination of one ormore such back end, middleware, or front end components. The componentsof the system can be interconnected by any form or medium of digitaldata communication, e.g., a communication network. Examples ofcommunication networks include a local area network (“LAN”) and a widearea network (“WAN”), e.g., the Internet.

The computing system can include clients and servers. A client andserver are generally remote from each other and typically interactthrough a communication network. The relationship of client and serverarises by virtue of computer programs running on the respectivecomputers and having a client-server relationship to each other.

The illustrations of the embodiments described herein are intended toprovide a general understanding of the structure of the variousembodiments. The illustrations are not intended to serve as a completedescription of all of the elements and features of apparatus and systemsthat utilize the structures or methods described herein. Many otherembodiments may be apparent to those of skill in the art upon reviewingthe disclosure. Other embodiments may be utilized and derived from thedisclosure, such that structural and logical substitutions and changesmay be made without departing from the scope of the disclosure.Additionally, the illustrations are merely representational and may notbe drawn to scale. Certain proportions within the illustrations may beexaggerated, while other proportions may be minimized. Accordingly, thedisclosure and the figures are to be regarded as illustrative ratherthan restrictive.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of the invention or of what may beclaimed, but rather as descriptions of features specific to particularembodiments of the invention. Certain features that are described inthis specification in the context of separate embodiments can also beimplemented in combination in a single embodiment. Conversely, variousfeatures that are described in the context of a single embodiment canalso be implemented in multiple embodiments separately or in anysuitable sub-combination. Moreover, although features may be describedabove as acting in certain combinations and even initially claimed assuch, one or more features from a claimed combination can in some casesbe excised from the combination, and the claimed combination may bedirected to a sub-combination or variation of a sub-combination.

Similarly, while operations are depicted in the drawings and describedherein in a particular order, this should not be understood as requiringthat such operations be performed in the particular order shown or insequential order, or that all illustrated operations be performed, toachieve desirable results. In certain circumstances, multitasking andparallel processing may be advantageous. Moreover, the separation ofvarious system components in the embodiments described above should notbe understood as requiring such separation in all embodiments, and itshould be understood that the described program components and systemscan generally be integrated together in a single software product orpackaged into multiple software products.

One or more embodiments of the disclosure may be referred to herein,individually and/or collectively, by the term “invention” merely forconvenience and without intending to voluntarily limit the scope of thisapplication to any particular invention or inventive concept. Moreover,although specific embodiments have been illustrated and describedherein, it should be appreciated that any subsequent arrangementdesigned to achieve the same or similar purpose may be substituted forthe specific embodiments shown. This disclosure is intended to cover anyand all subsequent adaptations or variations of various embodiments.Combinations of the above embodiments, and other embodiments notspecifically described herein, are apparent to those of skill in the artupon reviewing the description.

The Abstract of the Disclosure is provided to comply with 37 C.F.R.§1.72(b) and is submitted with the understanding that it will not beused to interpret or limit the scope or meaning of the claims. Inaddition, in the foregoing Detailed Description, various features may begrouped together or described in a single embodiment for the purpose ofstreamlining the disclosure. This disclosure is not to be interpreted asreflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter may be directed toless than all of the features of any of the disclosed embodiments. Thus,the following claims are incorporated into the Detailed Description,with each claim standing on its own as defining separately claimedsubject matter.

It is intended that the foregoing detailed description be regarded asillustrative rather than limiting and that it is understood that thefollowing claims including all equivalents are intended to define thescope of the invention. The claims should not be read as limited to thedescribed order or elements unless stated to that effect. Therefore, allembodiments that come within the scope and spirit of the followingclaims and equivalents thereto are claimed as the invention.

1. A method comprising: receiving data indicative of a location of amobile device; identifying a path based on the location of the mobiledevice; accessing characteristic information for the path; calculating,by a controller, a target route from the characteristic information forthe path; and determining whether the location of the mobile device or asubsequent location of the mobile device deviates from the path based ona comparison of the location of the mobile device to the target route.2. The method of claim 1, further comprising: adjusting the target routeaccording to an accuracy level of the data indicative of the location ofthe mobile device.
 3. The method of claim 2, wherein the accuracy levelis dependent on surroundings of the mobile device.
 4. The method ofclaim 2, further comprising: accessing a building model for an area nearthe mobile device; and calculating the accuracy level based on buildingmodel.
 5. The method of claim 1, wherein the characteristic informationincludes a functional classification of the path.
 6. The method of claim1, wherein the characteristic information includes a width of the path.7. The method of claim 1, wherein the historical data includes clustersof data points collected along the path and arranged based on proximity.8. The method of claim 1, wherein the historical data includes a transitschedule.
 9. The method of claim 1, further comprising: comparing adistance from the location of the mobile device to a border of thetarget route; and extending the border of the target route by a circleof error when the distance exceeds a threshold, wherein the circle oferror is based on the accuracy of position circuitry of the mobiledevice.
 10. An apparatus comprising: a memory configured to store targetroutes for a plurality of transit routes; and a controller configured toreceive data indicative of a location of a mobile device and configuredto access a target route based on the location of the mobile device,wherein a comparison of the target route and the location of the mobiledevice or a subsequent location of the mobile device determines whetherthe location of the mobile device deviates from the target route. 11.The apparatus of claim 10, wherein the target routes for the pluralityof transit routes are defined by path widths.
 12. The apparatus of claim11, wherein the path widths are based on functional classifications ofthe transit routes.
 13. The apparatus of claim 11, wherein the pathwidths are based on accuracy of a positioning system of the mobiledevice.
 14. The apparatus of claim 11, wherein the path widths are basedon a building model associated with the location of the mobile device.15. The apparatus of claim 11, wherein the path widths are based oncollected data from past trips on the plurality of transit routes. 16.The apparatus of claim 11, further comprising: positioning circuitryconfigured to generate the data indicative of the location of the mobiledevice.
 17. A non-transitory computer readable medium includinginstructions that when executed are operable to: receive data indicativeof a location of the mobile device at different times; identify a pathbased on the data indicative of the location of the mobile device;identify a target route based on characteristic information for thepath; and determining whether the mobile device deviates from the pathbased on a comparison of the location of the mobile device to the targetroute.
 18. The non-transitory computer readable medium of claim 17,wherein the characteristic information for the path includes afunctional classification of the path.
 19. The non-transitory computerreadable medium of claim 17, wherein the characteristic information forthe path includes a width of the path.
 20. The non-transitory computerreadable medium of claim 17, wherein the characteristic information forthe path includes an accuracy level of the data indicative of thelocation of the mobile device.
 21. The method of claim 1, wherein thecharacteristic information includes a functional classification of thepath based a width of the path.